1. Field
Example embodiments relate generally to an organic light emitting diode (OLED) display and a method for manufacturing the same and, more particularly, to an OLED display having an improved structure of an OLED, and a method for manufacturing the same.
2. Description of the Related Art
An active matrix type OLED display includes an organic light emitting element having a positive electrode, an organic emission layer, and a negative electrode, and a thin film transistor (TFT) for driving the organic light emitting element. In the active matrix type OLED display, holes injected from the positive electrode and electrons injected from the negative electrode are combined in the organic emission layer to generate excitons, and light is emitted by energy generated when the excitons fall to a base state from an excited state. The OLED display displays an image through such light emission.
The organic light emitting element may be formed as the organic emission layer, and the organic emission layer and the negative electrode may be sequentially stacked on the positive electrode connected with the TFT. In this structure, because the positive electrode is connected with the TFT, the TFT is a p-type TFT, and accordingly, a semiconductor layer of the TFT is made of polycrystalline silicon, e.g., formed by a crystallization process.
In this case, however, it is not easy to perform or obtain uniform crystallization, so the characteristics of the semiconductor layer formed thusly may not be uniform. Therefore, an OLED display having such a non-uniform semiconductor layer may have non-uniform light emission characteristics, and/or the OLED display may become defective. If the OLED display is increased in size, the problem would become more serious.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.